A brake disk stack comprises a plurality of stators disposed between a plurality of rotors. The rotors are connected to a vehicle wheel while the stators are fixed to, for example, a wheel support and brake. A brake employing such a disk stack acts by compressing the stack of rotors and stators to slow the rotors and the wheel attached to the rotors.
Various actuators are known for compressing a disk stack, among them, an EMA. FIG. 5 illustrates a braking system comprising a brake carrier 200 and a pressure plate 202 which forms part of a brake disk stack 204. An EMA 206 is mounted on the side of brake carrier 200 opposite disk stack 204 so that a piston 208 of the EMA 206 extends through an opening 210 in the brake carrier 200. Several openings 212, illustrated in FIG. 6, are provided in brake carrier 200 for receiving fasteners 214, such as screws or bolts, illustrated in FIG. 5.
In operation, piston 208 moves toward the brake disk stack 204 and presses against the pressure plate 202 which in turn compresses the rotors and stators in a well-known manner. The reactive force of this movement is borne by the four fasteners 214 which prevent the EMA 206 from separating from the carrier plate 200 and which must therefore be sized to reliably withstand what can be significant stresses.
To remove or attach EMA 206, fasteners 214 are removed, and EMA 206 is moved axially with respect to the brake carrier 200 until piston 208 is clear of opening 210. Because of the tight clearances in many devices employing such an arrangement, aircraft brakes, for example, it therefore is sometimes not possible to move EMA 206 axially a sufficient distance to allow the piston 208 to clear opening 210. It is therefore sometimes necessary to remove part or all of the disk stack 204, or other elements in the vicinity of the disk stack, to successfully remove the EMA 206. This complicates the repair or replacement of EMA 206.